# Copyright Huawei Technologies Co., Ltd. 2025-2025. All rights reserved.
import os
import json
import random
from PIL import Image
from tqdm import tqdm
import torch
import torchvision.transforms as T
from torchvision.transforms.functional import InterpolationMode

from example.common.security.path import get_valid_read_path

IMAGENET_MEAN = (0.485, 0.456, 0.406)
IMAGENET_STD = (0.229, 0.224, 0.225)


def build_transform(input_size):
    mean, std = IMAGENET_MEAN, IMAGENET_STD
    transform = T.Compose([
        T.Lambda(lambda img: img.convert('RGB') if img.mode != 'RGB' else img),
        T.Resize((input_size, input_size), interpolation=InterpolationMode.BICUBIC),
        T.ToTensor(),
        T.Normalize(mean=mean, std=std)
    ])
    return transform


def find_closest_aspect_ratio(aspect_ratio, target_ratios, width, height, image_size):
    best_ratio_diff = float("inf")
    best_ratio = (1, 1)
    area = width * height
    for ratio in target_ratios:
        target_aspect_ratio = ratio[0] / ratio[1]
        ratio_diff = abs(aspect_ratio - target_aspect_ratio)
        if ratio_diff < best_ratio_diff:
            best_ratio_diff = ratio_diff
            best_ratio = ratio
        elif ratio_diff == best_ratio_diff:
            if area > 0.5 * image_size * image_size * ratio[0] * ratio[1]:
                best_ratio = ratio
    return best_ratio


def dynamic_preprocess(image, min_num=1, max_num=12, image_size=448, use_thumbnail=False):
    orig_width, orig_height = image.size
    try:
        aspect_ratio = orig_width / orig_height
    except ZeroDivisionError as ex:
        logging.error('orig_height can not be zero. %s', str(ex))
        raise ex

    # calculate the existing image aspect ratio
    target_ratios = set()
    for n in range(min_num, max_num + 1):
        for i in range(1, n + 1):
            for j in range(1, n + 1):
                if i * j <= max_num and i * j >= min_num:
                    target_ratios.add((i, j))
    target_ratios = sorted(target_ratios, key=lambda x: x[0] * x[1])

    # find the closest aspect ratio to the target
    target_aspect_ratio = find_closest_aspect_ratio(
        aspect_ratio, target_ratios, orig_width, orig_height, image_size
    )

    # calculate the target width and height
    target_width = image_size * target_aspect_ratio[0]
    target_height = image_size * target_aspect_ratio[1]
    blocks = target_aspect_ratio[0] * target_aspect_ratio[1]

    # resize the image
    resized_img = image.resize((target_width, target_height))
    processed_images = []
    for i in range(blocks):
        box = (
            (i % (target_width // image_size)) * image_size,
            (i // (target_width // image_size)) * image_size,
            ((i % (target_width // image_size)) + 1) * image_size,
            ((i // (target_width // image_size)) + 1) * image_size
        )
        # split the image
        split_img = resized_img.crop(box)
        processed_images.append(split_img)
    if len(processed_images) != blocks:
        raise ValueError("The number of processed images does not match the expected number of blocks.")
    if use_thumbnail and len(processed_images) != 1:
        thumbnail_img = image.resize((image_size, image_size))
        processed_images.append(thumbnail_img)
    return processed_images


def load_image(image_file, input_size=448, max_num=12):
    image_file = get_valid_read_path(image_file, is_dir=False)
    image = Image.open(image_file).convert('RGB')
    transform = build_transform(input_size=input_size)
    images = dynamic_preprocess(image, image_size=input_size, use_thumbnail=True, max_num=max_num)
    pixel_values = [transform(image) for image in images]
    pixel_values = torch.stack(pixel_values)
    return pixel_values


def get_textvqa_calibration(textvqa_path, calib_num=30, get_all_calib=False):
    val_json = 'textvqa_val.jsonl'
    calibration_dataset = []
    
    val_json_path = os.path.join(textvqa_path, val_json)
    val_json_path = get_valid_read_path(val_json_path)
    with open(val_json_path, 'r') as file:
        for line in file:
            line_dict = json.loads(line.strip())
            line_dict['text'] = line_dict['question']
            line_dict['image_url'] = line_dict['image']
            calibration_dataset.append(line_dict)
    
    if not get_all_calib:
        calibration_dataset = random.sample(calibration_dataset, calib_num)
    
    return calibration_dataset


def get_tokenized_data(tokenizer, inputs, dtype=torch.float16):
    tokenization_data = []
    for _, input_item in tqdm(enumerate(inputs), total=len(inputs)):
        question = input_item.get('text')
        query = '<|im_start|>system\n你是由上海人工智能实验室联合商汤科技开发的书生多模态大模型，英文名叫InternVL, 是一个有用无害的人工智能助手。<|im_end|>' + \
        '<|im_start|>user\n<image>\n' + question + '<|im_end|><|im_start|>assistant\n'
        image_url = input_item['image_url']
        pixel_values = load_image(image_url, max_num=12).to('npu').to(dtype)
        generation_config = dict(max_new_tokens=1024, do_sample=False)
        tokenization_data.append([tokenizer, pixel_values, query, generation_config])
    return tokenization_data


def cmd_bool(cmd_arg):
    if cmd_arg == "True":
        return True
    elif cmd_arg == "False":
        return False
    raise ValueError(f"{cmd_arg} should be True or False")
